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1.
A cDNA encoding the Arabidopsis extraplastidic linoleate desaturase (FAD3) was overexpressed in the seeds of wild-type Arabidopsis and in a mutant line that accumulates high levels of oleic acid. In the transformed wild-type plants, linolenic acid (18:3Δ9,12,15) increased from 19% to nearly 40% of total seed fatty acids, with a corresponding decrease in linoleate content (18:2Δ9,12). In the high oleate mutant, a large increase in the level of a fatty acid identified by gas-chromatography/mass-spectrometry as mangiferic acid (18:2Δ9,15) was observed. The results demonstrate that the polymethylene-interrupted dienoic fatty acid, mangiferic acid, can be produced in seed oil through the overexpression of a fatty acid n-3 desaturase.
Mark A. SmithEmail:
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2.
1-Alkylamino-3-alkyloxy-2-propanols, V (a–g) and N,N-di-(2-hydroxy-3-alkyloxy propyl) alkylamines, VI (a–g) were prepared with the same chain length both for alkyl amino and alkyloxy groups by condensation of alkyl glycidyl ethers with long chain alkylamines by employing thermal and microwave-assisted methods. All the products were characterized by 1H-NMR, IR and fast atom bombardment mass spectrometry studies. These compounds were further sulfated and evaluated as their sodium salts for surfactant properties namely surface tension, critical micelle concentration, emulsifying property, wetting, foaming power and calcium tolerance. Sulfated 1-dodecylamino-3-dodecyloxy-2-propanol, VII c and sulfated N,N-di-(2-hydroxy-3-dodecyloxy propyl) dodecylamine, VIII c were found to exhibit superior surfactant properties among the respective series of monomers and dimers.
R. B. N. PrasadEmail:
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3.
A new group of surface active dicephalic derivatives of 1,3-dioxane, i.e., 2-alkyl-5,5-bis{[3-(N,N-dimethylamino)propyl]amido}-1,3-dioxane-di-N-oxides, were synthesized with high yields by the reaction of an appropriate 2-alkyl-5,5-bis-(carboxyethyl)-1,3-dioxane with an excess of N,N-dimethyl-1,3-propanediamine followed by oxidation with an aqueous solution of hydrogen peroxide. Structures and purity of all intermediates and final di-N-oxides were confirmed by means of 1H-NMR and ESI-MS spectroscopy. Synthesized compounds showed high surface activity with low values of critical micelle concentration and high effectiveness of surface tension reduction (γ CMC). However, only derivative with the longest 2-alkyl substituent showed good foaming and moderate emulsifying properties.
Andrzej PiaseckiEmail:
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4.
The introduction of pin-up oxygen on C60, such as in the oxidized fullerenes C60O and C60On, induced noticeable increase in the antioxidant activity as compared to pristine C60. The water-soluble inclusion complexes of fullerenes C60O and C60On reacted with linoleic acid peroxyl radical 1.7 and 2.4 times faster, respectively.
Ken KokuboEmail:
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5.
Fourteen pure β-aminopropionic acid amphoteric surfactants were synthesized from methyl acrylate using primary amines. The synthesis was done in two steps. First, Michael addition of a primary amine to methyl acrylate gave two separable addition products. Second, because the resulting esters gave, by the classical saponification procedure, undesired retro-Michael products, they were treated with sodium trimethylsilanolate to give the corresponding pure anhydrous acid salt under mild non-aqueous reaction conditions. Two types of amphoteric surfactants were obtained: the monocarboxylate and the dicarboxylate series. The pure surfactants were characterized by IR, 1H NMR, and 13C NMR spectroscopy. The surfactant critical micelle concentrations were evaluated. From these the Gibbs free energy of micellizations [∆G(–CH2–)mic] were calculated. These are related to the methylene units that contribute an average of −1.0 (±0.3) kJ mol−1 for both the monocarboxylate and the dicarboxylate series.
Gervais BérubéEmail:
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6.
A homologous series of new surface-active 1,1-bis{[3-(N,N-dimethylamino)ethyl]-amido}alkane-di-N-oxides were synthesized in the reaction of an appropriate diethyl 2-alkylmalonate with N,N-dimethylethylenediamine followed by oxidation with an aqueous solution of hydrogen peroxide. The adsorption isotherms of their aqueous solutions were measured and evaluated to obtain adsorption parameters: critical micelle concentration (CMC), surface excess concentration (ΓCMC), equilibrium surface tension at the CMC (γ CMC), cross-sectional area of the adsorbed surfactant molecule (A CMC), standard free energies of adsorption and micellization
Anna Krasowska (Corresponding author)Email:
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7.
A series of cationic surfactants, N-(decyl N-tri-ethanol ammonium Bromide) (C10), N-(dodecyl N-triethanol ammonium Bromide) (C12), N-(hexadecyl N-triethanol ammonium Bromide) (C16) were synthesized. These compounds have been evaluated by studying their surface properties, surface parameters, biodegradability and antimicrobial and antifungal activities.
D. A. IsmailEmail:
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8.
Quaternary ammonium salts (otherwise known as “quats”) commonly form the foundation of formulations in the antimicrobial industry. Many studies have been conducted on the biological activity of surfactants derived from fatty acids viz. lauric acid, myristic acid, stearic acid and palmitic acid and palm fatty acid with polyamine, i.e. 1(2-hydroxyethylpiperazine). The present paper investigates the synthesis and surface-active properties of esteramide quats derived from the esterification of the above-mentioned fatty acids and 1(2-hydroxyethylpiperazine) followed by quaternization using dimethyl sulphate (DMS). These derivatives were fully characterized by using Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance (NMR) spectroscopy, and 13C-NMR spectroscopy. In addition to the cationic content, surface tension, CMC (critical micelle concentration), fabric softening, rewettability, emulsification and dispersing power were determined as their surface-active properties.
Shilpi MishraEmail:
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9.
Application studies of novel saccharide-type nonionic surfactants were performed. The homolog series of N-alkyl-N-(2-hydroxyethyl)gluconamides and N-alkyl-N-(2-hydroxyethyl)glucoheptonamides (alkyl: n-C10H21, n-C12H25, and n-C14H29) were synthesized and their structures were confirmed by means of elemental analysis and 1H-NMR spectroscopy. The investigations showed that the application of N-alkyl-N-(2-hydroxyethyl)aldonamides as surfactants in an aqueous media can be limited. This is because of their relatively high Krafft point temperature. However, some variants can be successfully applied in mixtures with an anionic surfactant: sodium salt of n-dodecyl sulfate (SDS). The addition of SDS causes significant improvement of the Krafft point temperatures. In some cases a synergistic effect was observed, i.e., the Krafft point temperature of the binary mixture was lower that the corresponding values for the solutions containing individual compounds. It is also remarkable, that the aqueous solutions of binary surfactant mixtures were characterized by improved foaming properties, as compared to that of pure SDS.
Andrzej PiaseckiEmail:
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10.
Partitioning of Fatty Acids in Oil/Water Systems Analyzed by HPLC   总被引:1,自引:0,他引:1  
Surfactant/oil/water systems in which the surface-active substance is a mixture of an undissociated fatty acid (FA) and its sodium salt soap, exhibit the typical phase behavior and the general emulsion phenomenology produced by a formulation scan. The phase behavior transition is induced by changing the FA concentration in the system at a fixed alkaline (NaOH) content in water, which results in a variable lipophilic acid/hydrophilic salt ratio. The partitioning is reported for different FA types (octanoic to myristic) and alcohol co-surfactants between excess oil and water phases of Winsor three-phase optimum formulation system. The concentrations are determined by using a method reported in a previous work to quantify the total acid fraction in each phase.
Bélgica BravoEmail: Email:
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11.
A homologous series of new surface-active 1,1-bis{[3-(N,N-dimethylamino)propyl]amido}alkane-di-N-oxides were synthesized in the reaction of an appropriate diethyl 2-alkylmalonate with N,N-dimethylamino-1,3-propanediamine followed by oxidation with aqueous hydrogen peroxide. The adsorption isotherms of their aqueous solutions were measured and evaluated to obtain adsorption parameters: critical micelle concentration (CMC), surface excess concentration (ΓCMC), equilibrium surface tension at the CMC (γCMC), cross-sectional area of the adsorbed surfactant molecule (A CMC), efficiency of surface adsorption (pC20), standard free energies of adsorption (ΔG°ads), and micellization (ΔG°CMC). All investigated di-amidoamines and di-N-oxides were practically non-toxic to selected bacteria and yeasts. These compounds are readily biodegradable in the Closed Bottle Test inoculated with activated sludge. Surface and biological properties showed that this group of N-oxide-type compounds has high surface activity and fulfills requirements for environmental acceptance.
Andrzej PiaseckiEmail:
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12.
The properties of surfactin-C16 aqueous solution in the presence of Na+ ions, produced by Bacillus subtilis, were studied by the fluorescence method. The critical micelle concentration (CMC) of surfactin-C16 was measured as 24.7 μM in 0.05 M Tris buffer (pH 8.5–8.6). With an increase in Na+ concentration, the CMC value and micropolarity of surfactin-C16 decreased while the microviscosity increased, which means that the addition of Na+ improves the surface activity and enhances the micellization of the surfactin-C16 in solution. The preliminary aggregation number (N) was obtained by the steady-state fluorescence method.
Bo-Zhong MuEmail:
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13.
Low molecular weight resins containing relatively high levels of acrylic acid were converted to oxidatively curable materials by reacting the carboxylic acid groups with oxazoline functional alkenes. The oxazolines were obtained by reacting fatty acid with 2-amino-2-methyl-1-propanol. The oxazolines were then reacted with the acrylic resins at elevated temperature. Relatively high yields of the desired reaction products were obtained in relatively short reaction times. The resulting resins were formulated into aqueous coatings and films were made over metal substrates. The films were cured oxidatively and evaluated for property development. The films had good general solvent resistance but poor resistance to dilute sodium hydroxide.
D. L. TrumboEmail:
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14.
A SO4 2−/ZrO2 super acid was prepared and the effect of different kinds of catalysts on the esterification reaction reviewed. The results showed that the SO4 2−/ZrO2 super acid had higher catalytic activity and reactive selectivity in the synthesis of oleic acid polyglycol ester. Under optimum conditions the product was a monoester and the rate of production was more than 90%. The reaction product was characterized.
Tao-tao QiangEmail:
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15.
Silicate anions were studied using 29Si NMR to investigate the structure-directing effect of a surfactant (sodium dodecylsulfate-SDS) on the distribution of silicate species present in alkaline silicate solutions. The distribution of the anions in the presence of polyelectrolytes was also investigated by 29Si NMR through the use of different bases including tetramethyl ammonium hydroxide (TMAOH) and sodium hydroxide (NaOH). Both SDS and the polyelectrolytic solutions were shown to stabilize low molecular weight silicate species and thus inhibit polymerization.
Abdolraouf Samadi-MaybodiEmail:
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16.
A homologous series of surface active 2-(alkanoylamino)ethyldimethylamine-N-oxides, EDA-p(O), and 3-(alkanoylamino)propyldimethylamine-N-oxides, PDA-p(O), were synthesized. Their aqueous stock solutions were processed by the automatically operating apparatus to remove surface-active contamination and provide chemical purity at the air/water interface. In case of 3-(tetradecanoylamino)propyldimethylamine-N-oxide, PDA-14(O), the difference between equilibrium surface tension values of the purified surfactant solutions and the corresponding values of the solutions prepared from the “as received” compounds amounts to 15 mN m−1. Moreover, in presence of the surface-active contaminants time needed to reach equilibrium surface tension values is over 2 h. For the solution of the “surface-chemically pure” grade the change of the surface tension within adsorption time is negligible and the equilibrium is reached instantaneously. Physicochemical properties of obtained surface-chemically pure aqueous solutions of N-oxides of alkylamidoamines and adsorption parameters (standard free energy of adsorption, ΔG°ads, surface excess by saturation surface concentration, Γ, minimum surface area demand per molecule adsorbed, A min) were evaluated from the equilibrium surface tension versus concentration isotherms at the air/water interface using Gibbs’s equation. The introduction of the CH2 moiety into the intermediate part of molecule causes a slight decrease of the hydrophobic character of surfactant. Also the minimum surface area demand, A min, is slightly greater for PDA series than for the corresponding EDA derivatives. Surface potential measurements were performed in addition to surface tension studies. Electric surface potential versus concentration isotherms was determined. Surface potential increases with increasing surfactant’s bulk concentration for all investigated compounds. At highest concentrations, where interface is almost saturated, changes of surface potential become almost negligible.
Andrzej PiaseckiEmail:
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17.
New cationic surfactants, bis-quaternary ammonium salts, were prepared from N,N-dimethylaminoalkyl esters of saturated fatty acids and products of the reactions of epichlorohydrin with primary amines: pentyl-, hexyl- and octylamine. The bis (ester–ammonium) salts obtained were examined in respect to their surface-active properties: critical micelle concentration (CMC), effectiveness of surface tension reduction (γCMC), and adsorption efficiency (pC20). All these surfactants showed good water solubility and low critical micelle concentrations of more than two orders of magnitude lower than these of corresponding mono-alkylammonium salts. They also showed good wetting capability, but worse foaming properties. All the surfactants tested were nontoxic to gram-negative bacteria, but some of them inhibited the growth of gram-positive bacteria and yeast.
Jan ChlebickiEmail:
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18.
Short syntheses of (Z)-7-dodecen-1-yl acetate, (Z)-7-tetradecen-1-yl acetate, (Z)-9-dodecen-1-yl acetate, and (Z)-9-tetradecen-1-yl acetate from 7-hydroxyheptanal and 9-oxononanoic acid precursors obtained by oxidative cleavage of easily available aleuritic acid are reported. The key step in these syntheses is a stereoselective Wittig reaction between aldehyde and alkyl-phosphonium salt. Wittig-Horner type reaction of 7-hydroxyheptanal and diethyl cyanomethylphosphonate gave the ,-unsaturated nitrile derivative which after protection of the hydroxyl group was reduced to the corresponding aldehyde. Wittig reaction of the latter, followed by acetylation, completed the synthesis of (E,Z)-7,9-dodecadien-1-yl acetate, the sex pheromone of the European grapevine mothLobesia botrana Schiff.  相似文献   

19.
Sex attractants for the geometrid mothsEufidonia convergaria andCaripeta angustiorata, and the noctuid mothRivula propinqualis have been elucidated during field screening of a series of (3Z,6Z,9Z)-triene hydrocarbons (C17–22), and the racemic and enantiomerically enriched monoepoxydienes derived from those hydrocarbons. Biologically active compounds were identified by a combination of field testing of synthetic standards, electroantennography, and coupled gas chromatography-electroantennogram detection.E. convergaria males were optimally attracted by a 11 blend of (3Z,9Z)-(6S,7R)-epoxy-nonadecadiene (3Z,9Z-6S,7R-epoxy-19H); other abbreviations follow the same system) with (3Z,6Z,9Z)-nonadecatriene (3Z,6Z,9Z-19H). The 6R,7S enantiomer of the epoxide had no apparent biological activity, either as an attractant or as a behavioral antagonist. Male moths also were attracted to blends of the C18 and C20 homologs of the triene and the epoxide. 3Z,6Z,9Z-19H and 3Z,6Z-cis-6,7-epoxy-19H were identified inE. convergaria female pheromone gland extracts. Males of the geometrid moth speciesC. angustiorata were attracted by a 11 blend of 3Z,6Z,9Z-19H and enantiomerically enriched 3Z,9Z-6R,7S-epoxy-19H. Males of the noctuid mothR. propinqualis were attracted by an approximately 101 blend of 3Z,6Z,9Z-19H and enantiomerically enriched 3Z,9Z-6S, 7R-epoxy-19H. The components were synergistic, with neither being attractive alone. The blend ratio was quite specific, as the attractiveness of blends decreased sharply on either side of the optimum ratio.Issued as NRC No. 30266.  相似文献   

20.
A novel cationic gemini surfactant with the hydrophenanthrene structure has been synthesized from dehydroabietic acid by use of conventional thermal conditions and microwave irradiation. Its structure was confirmed by IR, 1H NMR, and 13C NMR spectroscopy. It was found that microwave-assisted synthesis is an efficient means of preparation of this cationic gemini surfactant, with shorter reaction times and higher yields. The title compound had high surface activity. The CMC was 3.1 × 10−5 mol L−1, γ CMC was 26.3 mN m−1, and emulsifying power (with benzene) reached five days. Comparison of this gemini surfactant and its monomeric counterpart proved the gemini surfactant was more surface active.
Zhanqian SongEmail:
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